By STEPHEN OHLEMACHERWASHINGTON (AP) â¿¿ Advocates for seniors say President Barack Obama is breaking his promise to protect Social Security, while conservatives say he is breaking his promise not to raise taxes on the middle class. Obama's budget proposal includes a mix of tax increases and benefit cuts in an effort to reduce government borrowing and spark the still-fragile economy. Obama says it is the kind of balanced approach that is necessary to tame runaway budget deficits. But advocates from across the political spectrum are reminding the president of his past campaign promises. "Clearly it will be up to members of Congress to set fiscal priorities that actually represent the needs of the average citizens they were elected to represent," said Max Richtman, head of the National Committee to Preserve Social Security and Medicare. "The president's budget is not the balanced plan promised to Americans before November's election." Obama's budget blueprint would increase taxes by $1 trillion over the next decade. Most of the tax increases would target wealthy households and corporations, though some, including a tax increase on cigarettes, would hit low- and middle-income families, too. At the same time, Obama's plan would trim benefit programs like Social Security and Medicare while adding new spending on infrastructure and early childhood education. The most sweeping proposal is to adopt a new measure of inflation for the government, which would gradually reduce benefits and raise taxes at the same time. Called the chained Consumer Price Index, the new measure would show a lower level of inflation than the more widely used Consumer Price Index. The change could have far-reaching effects because so many programs are adjusted each year based on year-to-year changes in consumer prices. Starting in 2015, Social Security recipients, military retirees and civilian federal retirees would get smaller benefit increases each year. Taxes would gradually go up because of smaller annual adjustments to income tax brackets, the standard deduction and the personal exemption amount.