By ALI SWENSON, Associated PressNEW YORK (AP) — Most Americans want Congress to extend tax credits that, if left to expire at the end of the year, could raise health insurance costs for millions of Americans, according to a new poll released Friday from the health care research nonprofit KFF. The vast majority of Democrats supported the extended tax credits, the poll found, but so did a slimmer majority of Republicans. According to the KFF poll, about 3 in 4 Americans — 78% — said that they wanted Congress to extend expiring tax credits for people who buy health insurance through the Affordable Care Act marketplace. About 6 in 10 people who have self-purchased insurance said they had heard “a little” or “nothing” about the tax credits’ expiration. Asked if they could afford nearly double the cost they pay in health insurance premiums, 70% of people who purchase insurance through the ACA Marketplace said they could not do this without significantly disrupting their household finances.