PHOENIX — One might think that BobMenendez.com would be the Web site of Senator Robert Menendez of New Jersey, chairman of the Democratic Senatorial Campaign Committee. But no. Sharron Angle, the Republican candidate for the Senate in Nevada, has the site, which her campaign uses to bash Democrats.

Likewise, BenQuayle.com has nothing to do with the candidacy of former Vice President Dan Quayle’s son, Ben, who is running for Congress in Arizona. Among the advertisers that have used the site is the Democratic National Committee, which promoted the accomplishments of President Obama, whom Ben Quayle has called history’s worst president.

At BradEllsworth.org, there are no kind words for Representative Brad Ellsworth, an Indiana Democrat who is running for the Senate. The site forwards visitors to BadforIndiana.com, run by the Indiana Republican Party, which criticizes Mr. Ellsworth as a “reliable rubber stamp for liberal policies.”

A survey by the Coalition Against Domain Name Abuse, a Washington-based trade group, has found that lawmakers are not as conscious of their online images as they ought to be.