This post card is published by the M. Kashower Company out of Los Angeles. It is from the "white border era" of post cards, which means it was printed between 1915 and 1930. That puts it in the right time zone because the company only existed from 1914 to 1934.
This route (The Golden State Limited) began running on November 2, 1902 from Chicago to Kansas City to El Paso, then it went on to New Mexico and Arizona and finally arrived in Los Angeles. It was a partnership between the Rock Island Line and the Southern Pacific. The journey was 2,762 miles long, making it the longest route in the United States. Canada had a route longer, so this was the second longest train route in North America. It took about 63 hours to complete the journey from Chicago to Los Angels. The Golden State Limited used Pullman passenger cars exclusively. The route began as a seasonal experience, but in 1910 the Golden State Limited began to run all through the year until its demise in 1968. Limited was dropped from the name in May of 1947.