Orrin Hatch, Charlie Rangel face key congressional primaries WASHINGTON -- Voters are heading to the polls for primary contests in key congressional races that could determine the fate of longtime incumbents -- and help define the new Congress that emerges after elections this fall. Veteran Republican Sen. Orrin Hatch is working to fend off a "tea party" challenge Tuesday in Utah, where conservative opponents have poured in money and resources in hopes of a repeat of their 2010 victory in the Beehive State that helped fuel the tea party victories nationwide that cycle. In New York's Harlem neighborhood, longtime Democratic Rep. Charles Rangel is in the fight of his political life as he seeks the primary nod for a 22nd term in the newly redrawn district that includes more Latino voters. Rangel faces several challengers, including state Sen. Adriano Espaillat, an upcoming Dominican American leader who has the backing of the president of the Dominican Republic. Neither of these races are considered pickups for the other party -- Utah is expected to elect a Republican senator in the fall, while New York's 13th House District will almost surely send a Democrat to Congress. Neither would likely tilt the balance of power in the House or Senate. But the outcomes Tuesday will provide other tests of this year's restive electorate -- and give shape to the new Congress. In Utah, the strength of the tea party, specifically the movement's leading umbrella group, FreedomWorks, will be challenged in the face of a highly prepared incumbent senator. Hatch, who is seeking a seventh term, has been preparing for this day for two years -- ever since conservatives knocked off his colleague, former Utah Sen. Robert Bennett, in one of the first surprise tea party victories of the 2010 wave. Hatch has been tacking to the political right in his votes and commentary, shoring up his support in the state and outspending his opponent, Dan Liljenquist, a former state senator, almost 10 to 1. Though Liljenquist is a conservative darling, Hatch was endorsed earlier this month by Sarah Palin, and is expected to clinch the nomination. GOP strategists suggest that the Utah race is a reminder that campaigns matter. They point to the defeat of Sen. Richard Lugar of Indiana, another veteran Republican who was challenged by the right flank and whose loss was attributed as much to an out- of-touch campaign as to any groundswell of tea party fervor in the Hoosier State. The New York race, meanwhile, offers a reminder of a different sort: that politics are, indeed, local. Rangel, who turned 82 this month, is challenged not so much by the ethics troubles that dogged his reelection two years ago, after he was censured by the House in connection with faulty tax filings on a home he owned in the Dominican Republic and other lapses. Rather, the shifting demographics of the district, which includes parts of the Bronx, are splitting the electorate along racial lines as the Latino voting-age population swelled with redistricting, according to the nonpartisan Cook Political Report. "If there is one incumbent in New York in the most primary jeopardy, it's Rangel," the Cook analysis said. Democrats in Washington endorsed Rangel, as it is the policy of the House Democratic campaign committee to back incumbents. But Democratic leaders are eyeing New York's upstate races, where the outcome of Tuesday primaries will lock in their candidates for the fall. Those races will be key battlegrounds in November, as Democrats target Republican-held districts in their effort to net 25 seats and retake the House majority -- a long-shot effort that will drive through the heart of the state.