WASHINGTON - As President Bush attempts to revive the controversial immigration reform bill he supports, the latest NBC News/Wall Street Journal poll finds that Republicans are abandoning the president, which has dropped his job-approval rating below 30 percent -- his lowest mark ever in the survey.

But he isn’t the only one whose support is on the decline in the poll. Congress’ approval rating has plummeted eight points, bringing it below even Bush’s. And just one in five believe the country is on the right track, which is the lowest number on this question in nearly 15 years.

Republican pollster Neil Newhouse, who conducted the survey with Democratic pollster Peter D. Hart, argues that these numbers have crossed below the political “Mendoza line,â€