A Rasmussen Reports survey conducted shortly after former Senator John Edwards announced last week that his wife's breast cancer had returned shows the Democratic presidential candidate leading Senator John McCain (R) 47% to 38%.

That’s far and away the biggest lead Edwards has enjoyed against the man who was once considered the Republican frontrunner. Throughout 2006, McCain led all Democrats in every general election match-up. Then, in January, Edwards moved ahead of McCain by three points. Last month Edwards and McCain were neck-and-neck.

The new national telephone survey also shows Edwards leading Massachusetts Republican Mitt Romney 55% to 29%. Though lopsided, the match-up represents only a modest gain for Edwards since February, when he dominated Romney 52% to 34%.

Senator Edwards is now viewed favorably by 57% of voters, including 53% of men, 61% of women. Thirty-five percent (35%) have an unfavorable opinion.

That's also the best showing for Edwards so far. Like other top-tier Democratic candidates, the Senator's unfavorable rating had lately been almost as high as his favorable rating. In mid-March he averaged 47% favorable, 45% unfavorable in our surveys (with the same ten-point discrepancy between men and women).

McCain is viewed favorably by 55%, unfavorably by 38%, numbers comparable to those of recent months.

Governor Romney is viewed favorably by 32%, unfavorably by 37%, a bit worse than his February numbers of 35% favorable, 31% unfavorable.

In the race for the Democratic nomination, Edwards has been consistently in third place. On the GOP campaign trail, Rudy Giuliani holds a solid lead over McCain. Mitt Romney consistently finishes fourth in Rasmussen Reports polling.

Rasmussen Reports provides weekly updates on the Presidential nomination competition, releasing new results for Democrats each Monday and for Republicans each Tuesday. In addition to tracking key issues Rasmussen Reports provides continuous updates on Republican and Democratic Presidential candidates, Congressional Leaders, Journalists, and other Political Figures. Rasmussen Reports also measures the President’s Job Approval on a daily basis.

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