NASHVILLE (AP) – Voters in Robertson and Sumner counties go to the polls Tuesday to select Republican Diane Black's permanent successor in the state Senate.

Black was elected to Congress in November, and her Senate District 18 seat has since been filled on a temporary basis.

Kerry Roberts, an accountant and bike store owner, won a six-way primary for the Republican nomination. He has lined up a series of endorsements from Republicans including Gov. Bill Haslam and Senate Speaker Ron Ramsey.

Portland Mayor Ken Wilber was unopposed for the Democratic nomination.

A Tennessee Tea Party e-mail on Monday characterized the race as "very close" and urged people to vote for Roberts and otherwise support his bid. Fewer than 4,000 ballots were cast in early voting.

Republicans hold a 20-13 majority in the Senate.

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