ABC News’ Rick Klein reports: Democrats have long been clamoring for President Obama to turn the focus to the economy, as he did starting today with a Labor Day rally in Wisconsin. Now, Republicans are eager to meet him on that same territory. With a major debate over taxes looming this fall, and Democrats lacking evidence of the long-promised economic turnaround, Republicans are entering the final stretch of the campaign optimistic about their chances if the discussion stays on jobs and the economy. In fact, Republicans are planning on turning the president’s announcement today — calling for an additional $50 billion in federal spending on infrastructure projects — against Democratic candidates. Starting Tuesday, according to Republican aides, Democratic candidates for House and Senate will be asked by Republicans nation-wide whether they support what amounts to a second round of stimulus spending – and whether they support more spending on top of the record deficits. Meanwhile, Democrats are set to make some harsh choices about their strongest candidates in the 2010 congressional races. Privately, Democratic strategists concede that a handful of incumbent House members are as good as gone, giving Republicans a head start in their effort to pick up the 39 seats they’d need to take control of the House this fall. The most endangered Democrats represent districts that represent rented territory – areas that Republicans have owned in the past, and are likely to take back in the future. That means that members of Congress who rode the Democratic waves in 2006 and 2008 are likely to be among the first washed out by the rising Republican tide in 2010. Members such as Rep. Suzanne Kosmas, D-Fla., Rep. Frank Kratovil, D-Md., and Rep. Betsy Markey, D-Colo., are in danger of seeing their candidacies cut off from national money, as strategists make tough calls about how to distribute limited resources. All three are freshman Democrats who have taken tough votes on behalf of the Obama agenda. But all three could see support from the Democratic Congressional Campaign Committee dry up if they don’t turn around their poll numbers. -Rick Klein UPDATE: UPDATE: The Democratic Congressional Campaign Committee is disputing suggestions that national Democrats are about to give up on any incumbent Democrats. When The New York Times reported Sunday that a decision to redirect resources away from the most endangered Democrats could come in the next two weeks, DCCC Chairman Chris Van Hollen issued a statement: “The DCCC is heavily invested in these campaigns. In each campaign mentioned, the DCCC has provided and continues to provide support for field operations and other key campaign activities,” said Van Hollen, D-Md.