To the purported short­list of certainties in life — death and taxes — add large, bipartisan support in the Senate for the farm bill.

Despite the pattern in recent years of intense partisan acrimony, backroom bickering and publicly staged fights over nearly every piece of legislation, the Senate has begun to plod through a nearly $1 trillion farm bill that is likely to get a bipartisan vote for its approval by week’s end.

If the coalition of Northern and Western senators holds together through dozens of amendments this week, it will yield the second large vote for a substantial piece of legislation in the polarized Senate in the past three months. In March, 74 senators, a majority of both Democrats and Republicans, supported a bill to continue the program that funds the federal highway and bridge construction program.