WASHINGTON — As Democrat Jon Tester headed for a surprise victory in his 2006 U.S. Senate race, he attacked his incumbent Montana Republican rival’s close ties to lobbyists and committed himself to a rigorous ethics standard. Now as he looks to win a fourth term in a race that could decide control of the Senate, Tester is embracing a practice he once held against his opponent: taking contributions from lobbyists and executives of corporations while helping craft a government spending package that directs billions of dollars. After Tester became chair of the Senate Defense Appropriations subcommittee in 2021, he received campaign contributions totaling over $160,000 from employees and committees representing the defense industry.