After slaying its 20,000 milestone this morning, the Dow Jones Industrial Average extended gains through the afternoon to make a play for 20,100.

The Dow rose 0.74% to 20,059. The blue-chip index was on track to close with its second consecutive day of triple-digit gains, a streak not seen since the two-day rally following the presidential election in November. 

The S&P 500 was up 0.75%, and the Nasdaq climbed 0.9%. All indexes were set to close at new records on Wednesday. 

What's next for the Dow now that it has topped 20,000? Find out here.

The road to 20,000 has been nail-biting. The Dow rose to within a point of the level on Jan. 6 before quickly backing off. The blue-chip index then withdrew from the milestone over the past several weeks on concerns over a Donald Trump administration's policies, particularly those concerning protectionist trade moves. It took 64 days for the Dow to reach 20,000 after passing 19,000 for the first time.

Read columnist Jim "Rev Shark" DePorre's take on Dow 20,000 here, or technical analyst Helene Meisler's view here.

Markets had rallied initially in the two months following Trump's unexpected win in November. Investors had placed big bets that a Trump administration would lead to higher infrastructure spending and looser financial regulations.

"Clarity is the markets' oxygen," said Quincy Krosby, market strategist at Prudential Financial. "The more President Trump provides, the more Dow 20000 moves to the rear-view mirror. Dow 21000 will soon become the next media obsession."

The Dow posted a triple-digit gain on Tuesday for the first time in three weeks, putting the index within 90 points of 20,000. The S&P 500 and Nasdaq closed at fresh records. Better-than-expected earnings from the likes of DuPont (DD - Get Report) and Alibaba (BABA - Get Report) drove gains, while President Donald Trump's executive orders on the Keystone XL pipeline set off a rally materials stocks.

Boeing (BA - Get Report) contributed the most to the Dow's gains after topping fourth-quarter profit estimates and guiding for an in-line 2017. The aerospace company earned an adjusted $2.47 a share, higher than consensus of $2.34 a share. Revenue of $23.29 billion exceeded estimates of $23.13 billion. Boeing anticipates full-year earnings between $9.10 and $9.30 a share, cupping estimates of $9.25. 

Caterpillar (CAT - Get Report) also led the Dow higher, rallying on the perceived benefits of a Trump infrastructure plan. Overnight, Trump took to Twitter overnight to foreshadow further details of his promise to build a wall along the Mexican border. 

Caterpillar also gained after reporting a slowdown in the decline of sales. Total global machine sales fell 10% in the rolling three-month period to December, compared to a 17% drop in November.

United Technologies ( UTX - Get Report) , a Dow component, fell on Wednesday after an in-line fourth quarter and after the company highlighted the potential for a series of acquisitions in 2017. The aerospace company earned an adjusted $1.56 a share, as analysts expected, while revenue of $14.66 billion came in just short of $14.71 billion consensus. United said it had bookmarked $1 billion to $2 billion for potential acquisitions this year, while also pegging $3.5 billion for stock buybacks.

Freeport-McMoRan (FCX - Get Report) shares fell on Wednesday afternoon after missing analysts' profit estimates. The company earned 25 cents a share, a dime below estimates. Freeport was also under pressure following an unfavorable court ruling in Indonesia against the firm. Indonesia's Papua province knocked back a company lawsuit seeking to cancel a $188 million claim for taxes.

Texas Instruments (TXN - Get Report) rose after reporting a double-digit percentage increase in quarterly profit. Earnings rose 26% over its recent quarter, while revenue rose 7.1%. Analog chip sales increased 10%, while embedded processor sales rose 6.3%.

Alcoa (AA - Get Report)  fell despite improving upon volume and sales over its recent quarter. Revenue climbed 3.5% to $2.54 billion over the recent quarter, above estimates of $2.46 billion. Alcoa said it anticipates global aluminium demand to increase by 4% this year. This quarter marked its first since splitting its business into two and separating from the units that produce manufactured goods.

Fourth-quarter earnings at Novartis (NVS - Get Report) missed analysts' expectations, though shares climbed after the pharmaceutical company launched a $5 billion share buyback and said it may sell its Alcon eye care unit. Novartis said core net income for the three months ended in December was $2.66 billion, marginally lower forecasts of $2.7 billion. The company said it was considering a "range" of options to boost shareholder value, including the sale of the Alcon division which generated about $5.8 billion in sales last year.

Seagate (STX - Get Report) surged after a better-than-expected quarter. The hard-drive tech company earned $1 a share over its recent quarter, sharply higher than 55 cents a share a year earlier. Adjusted earnings of $1.38 a share soared past estimates of $1.08 a share. Revenue of $2.89 billion came in above forecasts of $2.83 billion.

Brinker (EAT - Get Report) fell after warning of weaker sales at its restaurant chains over the full year. The owner of Chili's expects revenue to fall 2% to 2.5% this year, while same-store sales will likely drop 1.5% to 2%. Analysts expected flat full-year same-store sales. Fourth-quarter same-restaurant sales declined 3.1%, while revenue dropped 2.2%.

Crude oil prices fell Wednesday after a weekly reading on inventories showed a large build in the past week. Crude stocks rose by 2.8 million barrels in the week ended Jan. 20, far stronger than an expected increase of 300,000 barrels.

West Texas Intermediate crude declined 0.8% to $52.75 a barrel on Wednesday.