Virginia's Sen. Mark Warner has a nine-point lead over Republican challenger Ed Gillespie, a Quinnipiac University poll shows.

The survey released Thursday polls likely voters, which is considered a more accurate measure of a candidate’s support.

Warner, the former Democratic governor running for a second term, leads Gillespie 48 percent to 39 percent.

The race is far from decided, however, with 21 percent of voters in the poll saying they have not made up their minds about which candidate to support.

A RealClear Politics average shows Warner with an 18-point lead over Gillespie, the former head of the Republican National Committee and a one-time adviser to President George W. Bush.

The Quinnipiac poll shows a third candidate, Libertarian candidate Robert Sarvis, with 6 percent of the vote. Removed from the lineup, Warner holds onto his lead over Gillespie, this time with a 50-41 margin.

Poll assistant director Peter A. Brown said the new numbers show Warner remains popular in Virginia and is in “reasonable” shape for re-election on Nov. 4.

“But his lead is not insurmountable with six weeks to go until Election Day,” Brown added.

Brown said Warner and Gillespie are tied among independent voters, a key demographic. But Warner is better supported by Democrats than Gillespie by his Republican base.

“Warner’s reputation as one of the more conservative Democrats in the Senate may be making the difference here,” Brown said.

The poll shows Warner with a 52-34 favorably rating. Gillespie earned a 34-26 favorability rating, with a sizable 37 percent saying they do not know enough about him to make a judgment.

Voters also found Warner more “trustworthy” and “honest” than Gillespie, with margins of 57 percent, compared to just 39 percent for Gillespie.

Gillespie also trailed Warner when voters were asked which candidate “cares about their needs.”

Fifty-five percent of voters said Warner possessed that trait, compared with just 35 percent for Gillespie. Warner also beat Gillespie on “leadership qualities,” by a margin of 68 percent to 41 percent.

The poll's margin of error is plus or minus 3.1 percentage points. It surveyed 1,010 likely voters from Sept. 17-22.