With fewer than 100 days left before the fall elections, a look at the dozen most-competitive Senate races around the country shows a decided advantage for Democrats.

In addition to extending the Democratic majority, the Senate battles could also have a profound effect on the presidential race, given that four of the top pickup opportunities for Democrats are in swing states where Republican presidential candidates have traditionally done well — Virginia, Colorado, New Mexico and New Hampshire. President Bush won three of the four in 2004, losing only New Hampshire by a single percentage point to Democratic Sen. John Kerry from neighboring Massachusetts.

Congress Daily