Forty-three Republican senators on Monday joined the legal challenge to President Barack Obama’s actions on immigration, arguing that the president overstepped his constitutional authority in unilaterally expanding programs for immigrants. The White House has countered that Obama had no choice after comprehensive legislation that passed the Senate in 2013 stalled in the GOP-led House. The senators, led by Majority Leader Mitch McConnell, R-Ky., filed a friend-of-the-court brief in the case of United States v. Texas. A lawsuit from 26 states, led by Texas, challenges Obama’s actions, with the Supreme Court set to hear arguments later this month and possibly rule...